| 摘要 |
PROBLEM TO BE SOLVED: To correctly detect the residual energy which can be extracted from a series-parallel switching storage power supply, even if the connection is switched from a parallel to a series one, when the voltage drops. SOLUTION: As a series-parallel switching storage power supply 101, battery units are composed of a pair of storage batteries C11, C12 and C21, C22, each of which has its voltage dropped by a large amount as energy is taken out. The battery units are serially connected in a plurality of stages. As the voltage drops, the battery units are switched from a parallel connection to a series connection in stages, one step at a time, by means of switching means S11-S13, S21-S23. This system, being provided with a voltage detector for detecting the voltage, switching signal detectors S14, S24 for detecting switching signals for respective battery units, an operator 104 for making an operation, based on the detected voltage and switching signals, finds the residual energy of the series-parallel switching storage power supply 101 from the detected voltage in accordance with the switching conditions of the battery units. |
